Apparatus for cleaning the cavities of casting and the like

ABSTRACT

Automated apparatus for cleaning out manually inaccessible cavities of castings. The casting is placed on a work station or table and is held by side and top clamping members. An airborne stream of abrasive particles is now passed through the cavities, exiting through an opening in communication therewith. After a predetermined time clean air is blown through the casting along the same path as the abrasive material, thus to purge the casting of all foreign matter.

United States atent 1191 1111 3,869,830 Baker Mar. 11, 1975 [5 APPARATUSFOR CLEANING THE 3,309,818 3/1967, Brown 51/8 CAVITIES OF CASTING ANDTHE LIKE 3,769,752 11/1973 McDonald 51/14 UX [75] Inventor: Jesse L.Baker, Radford, Va.

[73] Assignee: The Mead Corporation, Dayton,

Ohio

[22] Filed: Sept. 28, 1973 [21] Appl. No.: 401,890

[52] U.S. Cl 51/8 R [51] Int. Cl. B24c 3/04, B240 3/32 [58] Field ofSearch 51/8 R, 8 SP, 14,5 R

[56] References Cited UNITED STATES PATENTS 1,890,164 12/1932Rosenberger 51/8 2,253,225 8/1941 Bowes 51/8 3,193,975 7/1965 Millhiser51/8 Primary Examiner-Donald G. Kelly Attorney, Agent, or Firm-Jennings,Carter & Thompson [5 7] ABSTRACT Automated apparatus for cleaning outmanually inaccessible cavities of castings. The casting is placed on awork station or table and is held by side and top clamping members. Anairborne stream of abrasive particles is now passed through thecavities, exiting through an opening in communication therewith. After apredetermined time clean air is blown through the casting along the samepath as the abrasive mate rial, thus to purge the casting of all foreignmatter.

5 Claims, 5 Drawing Figures PATENTEU 1 SHEET 3 [IF 3 CONTROL mil Tar;

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STOP

1 I STA R APPARATUS FOR CLEANING THE CAVITIES OF CASTING AND THE LIKE Myinvention relates to apparatus for cleaning the interior, generallyinaccessible cavities of castings and the like.

In the foundry arts castings such as cylinder heads for engines whichcontain coolant passages are generally cast by the use of removablecores of sand or the like. Thus, at the completion of the castingoperation it is required that all of the sand, fins and the like left inthe cavities be removed so that there will be no impediment to the flowof coolant when the part is assembled into an engine. As can beappreciated, these passages are extremely tortious in the sense thatthey must surround the parts of the head to be cooled, making itpractically impossible to ram out or otherwise mechanically to removethe remaining sand and fins. Therefore, my invention is directedparticularly to apparatus which is adapted to clean such cavities bypassing therethrough an airborne stream of an abrasive material such asabrasive steel shot.

My invention has as an object the provision of apparatus of thecharacter designated into which a casting, having cavities as aforesaid,may be placed, secured in place, a stream of the abrasive shot passedthrough the cavities in such fashion as to clean them out completely andthen, after the cleaning operation, to purge or completely clean thecavities of all remaining shot, dust, and other foreign bodies.

More in detail my improved apparatus comprises generally a table ontowhich the casting is placed. Many castings have openings in the sidesand bottom, communicating with the cavities and in some instances suchcastings also have openings in the top which also communicate with thecavities. In view of this my improved apparatus also comtemplates theprovision of means to hold the side openings in communication with meansto force the abrasive material into the casting and to hold the bottomopenings in communication with openings through the table for thedischarge of such material. Furthermore, when cleaning castings whichhave openings through their tops as well as their sides and bottoms, itis necessary to close off the top openings in such fashion that theabrasive material will follow the continuous circuit to be followed bythe coolant in the casting. My improved apparatus also embodies means tobe lowered down onto the top of the casting, while in place on thetable, thus to close any top openings and hold it more securely inplace, together with side clamps carried by such hold down means whichstraddle the casting and hold it still more further rigidly and firmlyin position during the cleaning operation.

My invention also contemplates the substantially complete automation ofthe cleaning operation in the sense that the abrasive material is blownthrough the casting for a certain, predetermined length of timeautomatically followed by the introduction of a purging, cleaning streamof air.

My invention further contemplates the provision of means to deliver andremove castings from the apparatus in the form of conveyors, togetherwith a stop memher which is in place when a casting is first delivered,thus to assure that it is aligned properly in the apparatus relative tothe direction of movement of the casting thereonto, together with meansto remove said stop member to permit a cleaned casting to be removedfrom the machine by means of a discharge conveyor.

Apparatus illustrating features of my invention is shown in theaccompanying drawings in which:

FIG. 1 is a front elevational view with certain parts broken away and insection;

FIG. 2 is a rear elevational view with certain parts broken away and insection;

FIG. 3 is a detail sectional view taken generally along line 3-3 of FIG.1 and showing further the addition of means to supply abrasive materialand clean air to the casting;

FIG. 4 is a side elevational view, drawn to a larger scale than theremaining figures with certain parts broken away for the sake ofclarity; and,

FIG. 5 is a wiring diagram.

Referring now to the drawings for a better understanding of my inventionthe same embodies a supporting framework 10 which may be in the form ofshapes embodying vertical legs and cross members 11. Across the top ofthe supporting framework is a heavy plate or table 12 which forms asupport for a casting C to be cleaned.

As best shown in FIG. 4 the castings are delivered to my improvedapparatus generally in the direction of the arrow 13, that is, pushed orotherwise moved onto the plate or support 12 from the delivery conveyor14. The castings are removed at the opposite side after being cleaned bypushing them onto a discharge conveyor 16 which takes them away forshipment, or other operatrons.

Mounted as a sort of superstructure over the support 12 is a frameworkcomprising vertical members 17 and another plate 18. The purpose of thissuperstructure is to support mechanism presently to be described whichis adapted to move down on top of a casting C in place on the support,thus to hold it down while it is being cleaned as will presently appear.

Mounted along one side of the table is an abutment in the form of aplate 19, the abutment having an opening 21 therethrough. See FIG. 3. Incommunication with the opening 21 is a conduit 22 through which theremay be passed an airborne stream of abrasive material such as shot or,alternatively, a supply of clean air. The details of this supplymechanism will be later described.

Mounted on the table, opposite the abutment 19 is a two-way pneumaticcylinder 23 having a piston rod 24. The piston rod 24 carries a clampingplate member 26 which is adapted as presently will appear, to push thecasting C to the right as viewed in FIG. 3 whereby the side openings inthe casting come into sealed communication with the opening 21 in theabutment 19, thus in effect connecting the cavity of the castingsubstantially airtight to the conduit 22.

Mounted on top of plate 18 is a double acting fluid pressure cylinder 27having a piston rod 28. Carried by the lower end of the piston rod is ahold down and clamping assembly indicated generally by the numeral Theunit 29 may comprise a plate 31 which is connected to the lower end ofthe piston rod 28. Pivotally mounted on the plate as at 32 and 33 areside clamp members 34 and 36 and secured to the clamp members 34 and 36are upstanding arms 37 and 38. The upper ends of the arms 37 are pivotedat 39 to the piston rod 41 of a double acting fluid pressure cylinder42. In similar manner, the arms 38 of the member 36 are pivoted at 43 tothe piston rod 44 of another double acting cylinder 46. Both of thecylinders 42 and 46 are mounted on the plate 31. As is shown in thedrawings when the piston rods 41 and 44 are retracted into theircylinders the respective side clamps are moved away from each other asshown in FIG. 4, whereby with the arms or clamps in this position thelowering of piston rod 28 lowers the clamps about a casting C in placeon the support 12. When the cylinders 42 and 46 are energized in anopposite direction the clamps 37 and 38 pivot inwardly toward eachother, clamping and holding the casting between them. At the same time,the casting is engaged at its top by the plate 31 which is lowered intoplace to press the casting downwardly onto the table, prior to movingthe clamps 37 and 38 inwardly.

From what has just been described it will be seen that when the partsmove from the full line position to the dotted line position of FIG. 4the clamping members 37 and 38 are moved first downwardly to straddlethe casting and thence inwardly to clamp it, while at the same time thecasting is pushed downwardly onto the top of the table 12 by the bottomof the plate 31. In order to stabilize the movement of the entire unit29 and to prevent it from rotating I provide guide members 47 secured tothe underside of the upper plate 18 between which the assembly 29slides, vertically.

The table 12 is provided with one or more openings 48 which are adaptedto communicate with bottom openings in the casting C. Thus, whenever thecasting C is in position on the table and clamped by the mechanismsdescribed opening 21 in the abutment 19 is in sealed communication witha side opening in the casting which communicates with its cavity orcavities and opening 48 is in communication with the bottom or dischargeopenings of the casting.

Secured beneath the plate or support 12 is a hopper 51 having adischarge pipe 52. As will later be explained, the abrasive material inthe form of shot passes through conduit 22 into the cavity throughopening 21 in the abutment l9 and thence through the cavities of thecasting and then through the opening 48 in the plate 12 and into thehopper 51. The material from hopper 51 may be conveyed through theconduit 52 to a storage place for reuse if desired.

Also mounted on the table is a double acting fluid pressure cylinder 53having a piston rod 54. The piston rod 54 carries on its outer end alocator member 56 which is adapted to move from the position shown inFIG. 3 to the right, whereby when a casting is moved into the machine inthe direction of arrow 13 the rear end of the casting engages theforward edge of the member 56, thus to accurately locate the position ofthe casting, in the direction of its movement into the machine. As willbe explained, while the casting is being cleaned the locator member 56is withdrawn from the path of the casting as shown in FIG. 3 and thepassage of the finished casting onto the discharge conveyor 16 actuatesa limit switch, to be described, to move the member 56 back intolocating position for the next casting.

While the apparatus shown herein may be operated by providing fluidunder pressure to the several cylinders and so forth, and usingindividual, manually controlled valves for the same, I prefer toautomate the operation so that it will operate more efficiently and moreaccurately. While various types and forms of control mechanisms may bedevised to do so, in FIG. 5 I show schemmatically a wiring diagram forcontrolling the various solenoid actuated valves, timers and relays andin which also is included various limit switches, all of which will nowbe described.

With the various switches, relays and parts in the position shown inFIG. 5 a casting has just been cleaned and purged and is now ready to bepushed from the plate 12 onto the discharge conveyor 16. Upon pushingthe casting, either manually or with mechanism not shown, onto conveyor16, in its passage along the conveyor the casting momentarily closes aswitch LS6. The closing of LS6 energizes a relay R2. The energization ofrelay R2 closes normally opened contacts 61 and 62. contacts 62, beingholding contacts and contacts 62 being used to energize a solenoid valve6. The solenoid valve 6 controls cylinder 53 and moves the piston rod 54and locator member 56 from the position shown in FIG. 3 to a positionsubstantially midway of the path of movement of a casting being pushedinto the machine in the direction of line 13.

With the locator member 56 now in place another casting to be cleaned ispushed from the conveyor 14 onto the table or support 12 until its endcontacts the edge of the'locator member 56. With the casting to becleaned in place the operator, now depresses the two start buttons 63and 64. The two start buttons are located so that the operator is forcedto use both hands to make the machine operate, thereby assuring that hishands are out of the way of the moving parts. Simultaneously depressingthe two start buttons 63 and 64 energizes control relay R1, opening itsnormally closed contact 66 and 67. The opening of contacts 66 of coursedeenergizes relay R2. Furthermore, the opening of contacts 67deenergizes the solenoid valve 6, energizing cylinder 53 in the oppositedirection and thus withdrawing the positive locating member 56 to theposition shown in FIG. 3. The withdrawing of the locating member 56closes limit switch LS5, thus to energize pneumatic timer T2 andsolenoid 1A. This energizes cylinder 27 in a direction to lower theentire vertically movable clamp assembly about the casting and alsoenergizes cylinder 23 in a direction to move the clamping member 26 tothe position shown in FIG. 3, namely, to a position where it is pressingthe casting against the abutment member 19. It will be noted that theclosing of LS5 energizes a timer T2. The energization of timer T2 alsocloses a set of off delay contacts 68, thus to ready the energization ofa circuit consisting of limit switches LS1. LS1A and solenoid valve 5,the latter of which will be energized to power cylinders 42 and 46 indirections to close the clamps 37 and 38. When the two clamp cylinders42 and 46 move to close the clamps, they actuate limit switches LS4 andLS4A. The closing of these switches energizes a timer T4 and this timeris set to allow the doors to clamp tightly before the actual cleaningoperation commences. The energization of timer T4 also closes a set ofcontact 69, thus to energize blow timer T1. As shown diagrammatically,timer T1 comprises a motor indicated by the letter M and a clutchindicated by CL. The energization of T1 I establishes a curcuit througha set of contacts 71 and to flow through the conduit 22, into thecasting, cleaning it, and to discharge downwardly into the hopper 51,through the opening 48. It will be noted, during all the timespreviously set forth the operator has had to hold both of the startbuttons 63 and 64 manually closed. However, upon energization of themixer, valve LS2 closes, by passing the start buttons and holding thecircuit energized. The operator can now release the two start buttons 63and 64. The time of the blast is determined by the time set on T1. WhenTl times out to stop the blasting, contacts 72 open and deenergize timerT3. Thus, off delay contacts 73 are now timing the opening of contacts72 to deenergize solenoid valves 2 and 3 to stop the air blast and theflow of shot. It will be noted that this time the mixing valve 74 is nowclosed. Now that no more shot is being applied it is now necessary toremove the shot remaining in the casting. Upon the timing out of T1 aset of contacts 77 closes, (it being remembered that contacts 73 at thistime are closed) thereby energizing solenoid valve 4. This introduces aflow of clean air into the cavity of the casting, which takes the samepath as did the abrasive material, thus to blow out any remaining shot,dust, and other fine particles left in the casting. When the mixer valve74 closes, limit switch LS2 opens, thereby to deenergize solenoids 1Aand timer T2. A normally closed set of contacts 68 controlled by T2 nowopens to deenergize solenoid 5, thus to power the cylinders 42 and 46 indirections to open the clamps 37 and 38. When the clamps open, limitswitches 4 and 4A open thus to reset T1 and T4. Also, the opening of theclamps opens limits swtich 3 and energizes solenoid valve 18, toenergize cylinder 27 for upward movement of the clamping unit 29 andalso to energize cylinder 23 in the direction to move clamp 26 to theleft as viewed in FIG. 3. The closing of limit switch 3 also energizestimer T5. When T5 times out, contacts 79 open, opening the circuit tosolenoid IE, to allow power to be applied to solenoid 1A when ready. Itwill here be noted that solenoids 1A and 1B are double solenoid valves,namely, ofthe type that when power is applied to the coil to shift thevalve, even though the power is subsequently removed, the valve wouldremain shifted until power is applied to the other coil. The casting isnow ready to be discharged from the machine, and in moving over LS6readies the machine to receive another casting.

From the foregoing it will be apparent that I have devised an improvedapparatus fully effective to clean the inner passageways of castings ofsand, fins, and other undesirable foreign material. In practice myinvention has proven to be extremely practical and satisfactory andfurthermore has proven to be capable of cleaning castings of suchintricate design that the same could hardly ever be cleaned by hand orotherwise.

While various velocities and sizes and types of abrasive materials maybe used by way of example I have found that for cleaning the passages orcavities of cast iron cylinder heads, I use abrasive steel shot and gritof a size to pass through a 12 to 18 size shiv or screen. The airpressure employed typically is 90 pounds per square inch, appliedthrough a one and one-half inch line 22.

While I have shown my invention in but one form, it will be obvious tothose skilled in the art that it is not so limited, but is susceptibleof various other changes and modifications without departing from thespirit thereof.

What I claim is:

1. In apparatus for cleaning internal cavities in castings and the likewherein there is at least one opening into a side of the castingcommunicating with at least one opening in the bottom of the casting,

a. a table on which the casting is placed, said table having an openingtherethrough in communication with the bottom opening in the castingwhen in place on the table,

b. a stationary abutment against which the side of the casting havingsaid opening therein is adapted to engage, there being an openingthrough the abutment in communication with the side opening in thecasting when in place on the table,

c. a power driven clamp member opposite the abutment adapted to pressthe side of the casting having the opening therein against the abutment,

d. a movable casting positioning member disposed to be engaged by an endof the casting when it is moved onto the table, thus accurately toposition the casting on-the table relative to the direction of itsmovement thereonto,

e. a power driven hold down member adapted to lower onto and engage thetop of the casting while in place on the table, and

f. means to force an airborne stream of abrasive material through theopenings in the abutment thence into said side opening in the casting,into the casting cavities and out through the bottom casting and tableopening, thus to clean said cavities.

2. Apparatus as defined in claim 1 in which there is means to stop theflow of said abrasive material and to purge the casting with a stream ofclean air which passes into and out of the casting along the flow pathof said abrasive material.

3. Apparatus as defined in claim 1 in which the power driven hold downmember includes arms disposed when the hold down member is moveddownwardly into contact with the top of the casting to straddle thecasting, and power means to move the arms toward each other, thus toclamp the casting between them, further securing the casting in placewhile it is being cleaned.

4. Apparatus as defined in claim 3 in which the power driven hold downmember includes material disposed to make a substantially airtight sealwith the top of the casting when lowered thereonto, whereby castingshaving openings through the upper surfaces may have such openings closedoff during the cleaning operation.

5. In apparatus for cleaning internal cavities in castings and the like,wherein there is at least one opening into a side of the casting with atleast one opening in the bottom of the casting,

a. a horizontally disposed table on which the casting is adapted to restand having an opening therethrough in communication with an opening inthe bottom of the casting,

b. delivery and discharge conveyors at opposite ends of the table bymeans of which the casting is delivered to and carried away from thetable,

c. a stationary abutment along one side of the table against which theside of the casting having said opening therein is adapted to engage,said abutment having an opening therethrough in communication with theside opening in the casting when the casting is in place on the table,

d. a power actuated clamp member opposite the abutment adapted to pressthe side of the casting having said opening therein against theabutment,

e. a casting positioning member located adjacent the discharge end ofthe table,

f. power means selectively to move the positioning member into the pathof the casting moving onto the table, thereby to stop it inpredetermined position thereon, and to withdraw the same, permitting thecasting to move onto the discharge conveyor,

g. a power driven hold down member mounted for vertical movement overthe table and adapted to be lowered onto the top of the casting while onthe table,

h. a pair of power actuated arms carried by the hold down memberdisposed to engage the casting between them after the hold down memberis lowered onto the casting,

. means to force an airborne stream of abrasive mameans to force cleanair through the casting cavities along the path set forth in (i) above,thus to purge the cavities of abrasive material.

1. In apparatus for cleaning internal cavities in castings and the likewherein there is at least one opening into a side of the castingcommunicating with at least one opening in the bottom of the casting, a.a table on which the casting is placed, said table having an openingtherethrough in communication with the bottom opening in the castingwhen in place on the table, b. a stationary abutment against which theside of the casting having said opening therein is adapted to engage,there being an opening through the abutment in communication with theside opening in the casting when in place on the table, c. a powerdriven clamp member opposite the abutment adapted to press the side ofthe casting having the opening therein against the abutment, d. amovable casting positioning member disposed to be engaged by an end ofthe casting when it is moved onto the table, thus accurately to positionthe casting on the table relative to the direction of its movementthereonto, e. a power driven hold down member adapted to lower onto andengage the top of the casting while in place on the table, and f. meansto force an airborne stream of abrasive material through the openings inthe abutment thence into said side opening in the casting, into thecasting cavities and out through the bottom casting and table opening,thus to clean said cavities.
 1. In apparatus for cleaning internalcavities in castings and the like wherein there is at least one openinginto a side of the casting communicating with at least one opening inthe bottom of the casting, a. a table on which the casting is placed,said table having an opening therethrough in communication with thebottom opening in the casting when in place on the table, b. astationary abutment against which the side of the casting having saidopening therein is adapted to engage, there being an opening through theabutment in communication with the side opening in the casting when inplace on the table, c. a power driven clamp member opposite the abutmentadapted to press the side of the casting having the opening thereinagainst the abutment, d. a movable casting positioning member disposedto be engaged by an end of the casting when it is moved onto the table,thus accurately to position the casting on the table relative to thedirection of its movement thereonto, e. a power driven hold down memberadapted to lower onto and engage the top of the casting while in placeon the table, and f. means to force an airborne stream of abrasivematerial through the openings in the abutment thence into said sideopening in the casting, into the casting cavities and out through thebottom casting and table opening, thus to clean said cavities. 2.Apparatus as defined in claim 1 in which there is means to stop the flowof said abrasive material and to purge the casting with a stream ofclean air which passes into and out of the casting along the flow pathof said abrasive material.
 3. Apparatus as defined in claim 1 in whichthe power driven hold down member includes arms disposed when the holddown member is moved downwardly into contact with the top of the castingto straddle the casting, and power means to move the arms toward eachother, thus to clamp the casting between them, further securing thecasting in place while it is being cleaned.
 4. Apparatus as defined inclaim 3 in which the power driven hold down member includes materialdisposed to make a substantially airtight seal with the top of thecasting when lowered thereonto, whereby castings having openings throughthe upper surfaces may have such openings closed off during the cleaningoperation.